<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        var age = 20;
        age = 10;

        var user = {
            name: '张三',
            age: 52,
            sex: '男'
        }

        user.age = 22;
        // 删除对象的属性
        delete user.sex;
        console.log('user',user);
    </script>
</body>
</html>